This project will develop a simple, easy to use system which projects a three dimensional image of the position of a colonoscope onto a video screen next to the endoscopic image of the lumen. This system will play a major role in guiding colonoscopes through the colon to the cecum. It will increase the efficiency of colonoscopy, save time, and possibly decrease morbidity due to the procedure by reducing excess looping in the colon, a significant factor in colonic perforation. Specific goals for this phase II project are: l) complete a full-fledged commercial version of the colonoscope spatial imaging sensor, 2) complete human trials, 3) develop a manufacturing process to guarantee the quality, durability, and measuring accuracy of the sensor system, 4) develop the clinical procedure for using the instrument. This project will lead to a completed version of the endoscopic image detector instrument, completion of a series of human trials, and fulfillment of all the clinical and engineering requirements for the commercial launching of the product in Phase III. PROPOSED COMMERCIAL APPLICATION: This device will provide endoscopy units a stand alone and easy-to-use tool for spatial imaging of colonoscopes at very low cost. Since only fluoroscopy is currently available in most endoscopy units to obtain colonoscope images and considering the application of this device for surgeons, internists, family practitioners, and teaching programs, the commercial possibilities of this device are great.